This invention relates to ball pitching machines and particularly to such a machie for pitching a baseball in an accurately predetermined direction.
Baseball pitching machines of the type heretofore available have almost universally employed a pair of oppositely rotating pneumatic tires between which a baseball is received for propelling or pitching the baseball in a trajectory tangential to the tire peripheries. The pneumatic tires are closely enough spaced to compress as they receive the baseball therebetween and will impel the baseball at a velocity determined by the speed of rotation of the tires. Great care must be taken to insure proper inflation of the tires so they will properly receive the baseball, but even if care is taken and the baseball is correctly channeled between the pneumatic tires, there is considerable danger of the ball sliding off to one side or the other and being projected sidewise of a plane containing the two tires. This situation can become especially pronounced as the pneumatic pressure in one or both of the tires lessens. Moreover, irregularities in the pneumatic tires and particularly the tread portions affects the direction the baseball is pitched.
Most known baseball pitching machine locate both of the ball engaging pneumatic tires in a horizontal plane, or at most at some angle to the horizontal. It would be desirable to be able to position the ball engaging wheels in a vertical plane for more accurately simulating many of the balls actually thrown by a human pitcher, but a batter is justifiably wary of such an arrangement because of the danger of being struck by the baseball.
Tennis ball propelling machines have been proposed which include vertically disposed ball engaging wheels, but depend upon the compressibility of the tennis ball for their operation. Thus, a pair of rigid ball projecting wheels may be closely enough spaced so that the tennis ball is securely compressed between the wheel peripheries to be thrown outwardly as the wheels rotate in opposite directions. However, wheels of this type are obviously inappropriate for throwing a much harder baseball. While wheels of some tennis ball projecting machines or the like have been provided with a friction coating or layer to insure adequate engagement of the ball without slippage, such frictional coatings are not generally compressible to a degree for adequately receiving a hard baseball, while at the same time being capable of consistently projecting the baseball in a desired direction.